Question 1

Which of the following is not a carrier molecule that carries hydrogen atoms or electrons in oxidative reactions?

Accepted Answer

A) Cytochrome 
B) FAD 
C) Niacin 
D) NAD⁺ 
A) Cytochrome 
B) FAD 
C) Niacin 
D) NAD⁺

Question 2

As electrons are passed from carrier to carrier,their energy changes.At which point in the chain would you expect the energy of the electrons to be the highest?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) E 
A) A 
B) B 
C) C 
D) D 
E) E

Question 3

Enzymes work by:

Accepted Answer

A) lowering the energy of the reactants. 
B) raising the energy of the products. 
C) decreasing the activation energy of the reaction. 
D) increasing the activation energy of the reaction. 
A) lowering the energy of the reactants. 
B) raising the energy of the products. 
C) decreasing the activation energy of the reaction. 
D) increasing the activation energy of the reaction.

Question 4

Oxidation is defined as the ________ while reduction is the ________ .

Accepted Answer

A) gain of electrons, loss of protons 
B) loss of electrons, gain of protons 
C) loss of electrons, gain of electrons 
D) loss of protons, gain of protons 
A) gain of electrons, loss of protons 
B) loss of electrons, gain of protons 
C) loss of electrons, gain of electrons 
D) loss of protons, gain of protons

Question 5

At which temperature do enzymes begin to denature?

Accepted Answer

A) 20 degrees Celsius 
B) 30 degrees Celsius 
C) 40 degrees Celsius 
D) 50 degrees Celsius 
A) 20 degrees Celsius 
B) 30 degrees Celsius 
C) 40 degrees Celsius 
D) 50 degrees Celsius

Question 6

A surfactant:

Accepted Answer

A) lowers the surface tension at the bacterium's posterior end allowing Myxococcus to glide 
B) is metabolized to produce phosphoenolpyruvate 
C) forms channels through the outer membrane 
D) emits light as it returns to its unexcited state 
A) lowers the surface tension at the bacterium's posterior end allowing Myxococcus to glide 
B) is metabolized to produce phosphoenolpyruvate 
C) forms channels through the outer membrane 
D) emits light as it returns to its unexcited state

Question 7

During the metabolism of fats,the product of beta-oxidation enters:

Accepted Answer

A) glycolysis 
B) Krebs cycle 
C) oxidative phosphorylation 
D) electron transport chain 
A) glycolysis 
B) Krebs cycle 
C) oxidative phosphorylation 
D) electron transport chain

Question 8

The first step in protein metabolism is the breakdown of proteins into:

Accepted Answer

A) nucleotides 
B) fatty acids 
C) amino acids 
D) coenzymes 
A) nucleotides 
B) fatty acids 
C) amino acids 
D) coenzymes

Question 9

Chemiosmosis:

Accepted Answer

A) forms ATP 
B) occurs in the cell membrane of prokaryotes 
C) uses a proton gradient to activate ATP synthase 
D) all the above 
A) forms ATP 
B) occurs in the cell membrane of prokaryotes 
C) uses a proton gradient to activate ATP synthase 
D) all the above

Question 10

Which of the following statements about enzyme inhibition is true?

Accepted Answer

A) Most noncompetitive inhibitors bind to several different sites on an enzyme. 
B) Enzymes become less efficient as temperatures drop because they begin to denature. 
C) Noncompetitive inhibitors bind to a site other than the active site. 
D) Most human enzymes have an optimum temperature below normal body temperature. 
A) Most noncompetitive inhibitors bind to several different sites on an enzyme. 
B) Enzymes become less efficient as temperatures drop because they begin to denature. 
C) Noncompetitive inhibitors bind to a site other than the active site. 
D) Most human enzymes have an optimum temperature below normal body temperature.

Question 11

Which statement is true about enzymes?

Accepted Answer

A) Enzyme-catalyzed reactions would not go forward without their specific enzymes. 
B) Most enzymes catalyze several different reactions. 
C) Coenzymes are organic molecules while cofactors are inorganic molecules. 
D) A holoenzyme is an apoenzyme that is missing its cofactor. 
A) Enzyme-catalyzed reactions would not go forward without their specific enzymes. 
B) Most enzymes catalyze several different reactions. 
C) Coenzymes are organic molecules while cofactors are inorganic molecules. 
D) A holoenzyme is an apoenzyme that is missing its cofactor.

Question 12

How is ATP formed by chemiosmosis?

Accepted Answer

A) Proton gradient across a membrane provides motive force 
B) Nitrates are used as their final electron acceptor 
C) The last step involves H₂O to be split into O₂ 
D) All of the metabolites enter the Krebs cycle 
A) Proton gradient across a membrane provides motive force 
B) Nitrates are used as their final electron acceptor 
C) The last step involves H₂O to be split into O₂ 
D) All of the metabolites enter the Krebs cycle

Question 13

In algae,the dark reactions of photosynthesis occur in the:

Accepted Answer

A) cell membrane 
B) matrix of the mitochondria 
C) stroma of the chloroplast 
D) nucleus 
A) cell membrane 
B) matrix of the mitochondria 
C) stroma of the chloroplast 
D) nucleus

Question 14

Competitive inhibition of enzymes occurs when the inhibitor:

Accepted Answer

A) binds to the active site of the enzyme. 
B) binds to the allosteric site of the enzyme. 
C) changes the shape of the enzyme. 
D) is acted upon by the enzyme. 
A) binds to the active site of the enzyme. 
B) binds to the allosteric site of the enzyme. 
C) changes the shape of the enzyme. 
D) is acted upon by the enzyme.

Question 15

All of the following are electron acceptors for anaerobic respiration,except:

Accepted Answer

A) carbon dioxide 
B) oxygen 
C) nitrate ions 
D) sulfate ions 
A) carbon dioxide 
B) oxygen 
C) nitrate ions 
D) sulfate ions

Question 16

Sulfa drugs bind to the active site of the enzyme which normally converts para-amino benzoic acid (PABA)to folic acid,preventing the production of folic acid and,eventually purine synthesis. In this case,the sulfa drug is acting as a/an:

Accepted Answer

A) allosteric inhibitor 
B) competitive inhibitor 
C) noncompetitive inhibitor 
D) uncompetitive inhibitor 
A) allosteric inhibitor 
B) competitive inhibitor 
C) noncompetitive inhibitor 
D) uncompetitive inhibitor

Question 17

A holoenzyme can consist of:

Accepted Answer

A) an apoenzyme plus a cofactor 
B) an apoenzyme plus a coenzyme 
C) a protein and non-protein component 
D) all of the above 
A) an apoenzyme plus a cofactor 
B) an apoenzyme plus a coenzyme 
C) a protein and non-protein component 
D) all of the above

Question 18

In photosynthesis,light energy is used to:

Accepted Answer

A) break down proteins 
B) phosphorylate ADP to form ATP 
C) synthesize carbohydrates 
D) two of these choices 
A) break down proteins 
B) phosphorylate ADP to form ATP 
C) synthesize carbohydrates 
D) two of these choices

Question 19

The initial substrate molecule for the Krebs cycle is:

Accepted Answer

A) pyruvic acid 
B) acetyl-CoA 
C) acetic acid 
D) butanediol 
A) pyruvic acid 
B) acetyl-CoA 
C) acetic acid 
D) butanediol

Question 20

Which statement about fermentation is true?

Accepted Answer

A) All fermentation of pyruvic acid always results in the same end product. 
B) All fermentation starts with glucose going through glycolysis. 
C) The same fermentation reaction produces both wine and cheese. 
D) None of the above 
A) All fermentation of pyruvic acid always results in the same end product. 
B) All fermentation starts with glucose going through glycolysis. 
C) The same fermentation reaction produces both wine and cheese. 
D) None of the above

Exam 5: Essential Concepts of Metabolism

Which of the following is not a carrier molecule that carries hydrogen atoms or electrons in oxidative reactions?

As electrons are passed from carrier to carrier,their energy changes.At which point in the chain would you expect the energy of the electrons to be the highest?

Enzymes work by:

Oxidation is defined as the ________ while reduction is the ________ .

At which temperature do enzymes begin to denature?

A surfactant:

During the metabolism of fats,the product of beta-oxidation enters:

The first step in protein metabolism is the breakdown of proteins into:

Chemiosmosis:

Which of the following statements about enzyme inhibition is true?

Which statement is true about enzymes?

How is ATP formed by chemiosmosis?

In algae,the dark reactions of photosynthesis occur in the:

Competitive inhibition of enzymes occurs when the inhibitor:

All of the following are electron acceptors for anaerobic respiration,except:

Sulfa drugs bind to the active site of the enzyme which normally converts para-amino benzoic acid (PABA)to folic acid,preventing the production of folic acid and,eventually purine synthesis. In this case,the sulfa drug is acting as a/an:

A holoenzyme can consist of:

In photosynthesis,light energy is used to:

The initial substrate molecule for the Krebs cycle is:

Which statement about fermentation is true?

Scope and History of Microbiology

Fundamentals of Chemistry

Microscopy and Staining

Characteristics of Prokaryotic and Eukaryotic Cells

Growth and Culturing of Bacteria

Microbial Genetics

Gene Transfer and Genetic Engineering

An Introduction to Taxonomy: the Bacteria

Viruses

Eukaryotic Microorganisms and Parasites

Sterilization and Disinfection

Antimicrobial Therapy

Host-Microbe Relationships and Disease Processes

Epidemiology and Nosocomial Infections

Innate Host Defenses

Immunology I: Basic Principles of Adaptive Immunity and Immunization

Immunology Ii: Immunological Disorders and Tests

Diseases of the Skin and Eyes; Wounds and Bites

Urogenital and Sexually Transmitted Diseases

Diseases of the Respiratory System

Oral and Gastrointestinal Diseases

Cardiovascular, lymphatic and Systemic Disease

Diseases of the Nervous System

Environmental Microbiology

Applied Microbiology

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Oxidation is defined as the while reduction is the .